Double Moon Illusion
Enceladus and Dione, as seen by Cassini. Credit: NASA/JPL/Space Science Institute
We’ve all experienced the Moon Illusion, where our own full Moon looks bigger when seen on the Earth’s horizon. But how about this illusion where you can’t really tell which of these two moons of Saturn is actually bigger, or which is closer, as seen by the Cassini spacecraft? Here, Dione, top right, appears closer to the spacecraft because it is larger than the moon Enceladus, lower left. However, Enceladus was actually closer to Cassini when its visible light, narrow-angle camera took this image. (…) Read the rest of Double Moon Illusion (92 words)
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(C) nancy for Universe Today, 2011. | Permalink | One comment | Add to del.icio.us Post
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